From 85c675d0d09a45a135bddd15d7b385f8758c32fb Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 18 May 2024 19:35:05 +0200 Subject: Adding upstream version 6.7.7. Signed-off-by: Daniel Baumann --- drivers/tty/n_tty.c | 77 +++++++++++++++++++++++++---------------------------- 1 file changed, 36 insertions(+), 41 deletions(-) (limited to 'drivers/tty/n_tty.c') diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 6c9a408d67..f252d0b5a4 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -249,15 +249,12 @@ static void n_tty_check_throttle(struct tty_struct *tty) if (ldata->icanon && ldata->canon_head == ldata->read_tail) return; - while (1) { - int throttled; + do { tty_set_flow_change(tty, TTY_THROTTLE_SAFE); if (N_TTY_BUF_SIZE - read_cnt(ldata) >= TTY_THRESHOLD_THROTTLE) break; - throttled = tty_throttle_safe(tty); - if (!throttled) - break; - } + } while (!tty_throttle_safe(tty)); + __tty_set_flow_change(tty, 0); } @@ -279,16 +276,14 @@ static void n_tty_check_unthrottle(struct tty_struct *tty) * we won't get any more characters. */ - while (1) { - int unthrottled; + do { tty_set_flow_change(tty, TTY_UNTHROTTLE_SAFE); if (chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE) break; + n_tty_kick_worker(tty); - unthrottled = tty_unthrottle_safe(tty); - if (!unthrottled) - break; - } + } while (!tty_unthrottle_safe(tty)); + __tty_set_flow_change(tty, 0); } @@ -1965,26 +1960,27 @@ static bool copy_from_read_buf(const struct tty_struct *tty, u8 **kbp, size_t head = smp_load_acquire(&ldata->commit_head); size_t tail = MASK(ldata->read_tail); - n = min(head - ldata->read_tail, N_TTY_BUF_SIZE - tail); - n = min(*nr, n); - if (n) { - u8 *from = read_buf_addr(ldata, tail); - memcpy(*kbp, from, n); - is_eof = n == 1 && *from == EOF_CHAR(tty); - tty_audit_add_data(tty, from, n); - zero_buffer(tty, from, n); - smp_store_release(&ldata->read_tail, ldata->read_tail + n); - /* Turn single EOF into zero-length read */ - if (L_EXTPROC(tty) && ldata->icanon && is_eof && - (head == ldata->read_tail)) - return false; - *kbp += n; - *nr -= n; - - /* If we have more to copy, let the caller know */ - return head != ldata->read_tail; - } - return false; + n = min3(head - ldata->read_tail, N_TTY_BUF_SIZE - tail, *nr); + if (!n) + return false; + + u8 *from = read_buf_addr(ldata, tail); + memcpy(*kbp, from, n); + is_eof = n == 1 && *from == EOF_CHAR(tty); + tty_audit_add_data(tty, from, n); + zero_buffer(tty, from, n); + smp_store_release(&ldata->read_tail, ldata->read_tail + n); + + /* Turn single EOF into zero-length read */ + if (L_EXTPROC(tty) && ldata->icanon && is_eof && + head == ldata->read_tail) + return false; + + *kbp += n; + *nr -= n; + + /* If we have more to copy, let the caller know */ + return head != ldata->read_tail; } /** @@ -2154,9 +2150,8 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, u8 *kbuf, struct n_tty_data *ldata = tty->disc_data; u8 *kb = kbuf; DEFINE_WAIT_FUNC(wait, woken_wake_function); - int c; int minimum, time; - ssize_t retval = 0; + ssize_t retval; long timeout; bool packet; size_t old_tail; @@ -2192,9 +2187,9 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, u8 *kbuf, return kb - kbuf; } - c = job_control(tty, file); - if (c < 0) - return c; + retval = job_control(tty, file); + if (retval < 0) + return retval; /* * Internal serialization of reads. @@ -2499,7 +2494,7 @@ static int n_tty_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg) { struct n_tty_data *ldata = tty->disc_data; - int retval; + unsigned int num; switch (cmd) { case TIOCOUTQ: @@ -2507,11 +2502,11 @@ static int n_tty_ioctl(struct tty_struct *tty, unsigned int cmd, case TIOCINQ: down_write(&tty->termios_rwsem); if (L_ICANON(tty) && !L_EXTPROC(tty)) - retval = inq_canon(ldata); + num = inq_canon(ldata); else - retval = read_cnt(ldata); + num = read_cnt(ldata); up_write(&tty->termios_rwsem); - return put_user(retval, (unsigned int __user *) arg); + return put_user(num, (unsigned int __user *) arg); default: return n_tty_ioctl_helper(tty, cmd, arg); } -- cgit v1.2.3